The difficulties of obtaining human corneas to make satisfactory antigen in adequate quantity to study cellular and humoral immunity prompted pilot experiments with animal tissues. Ouchterlony immunodiffusion showed identical precipitating bands among corneal proteins from human and animal corneas when tested against antiserum raised in rabbits against the soluble proteins of human cornea. Other laboratories have suggested that many antigens among the soluble and structural proteins of human and animal corneas may not be species specific. It is proposed to characterize the soluble and insoluble antigens of human and calf cornea and determine which ones are tissue specific and species specific. If non-species proteins or peptides can be shown to constitute the principal antigens responsible for humoral and cellular immunity, animal, i.e. calf, corneas may be utilized to facilitate the study of immune reactions. Immunologic mechanisms may play an important role in the pathophysiology of chronic keratopathies and corneal transplantation reactions.